Expanding arbors



Oct. 25, 1966 R. w. ANTHONY 3,280,675

EXPANDING ARBORS Original Filed June 28, 1965 FIG. I

INVENTOR. RUSSEL W. ANTHONY United States Patent Ofiiice 3,280,675 Patented Oct. 25, 1966 2 Claims. (CI. 82-44) The present application relates to expanding arbors and is a division of my copending application Serial No. 467,239, filed June 28, 1965.

It is an object of the present invention to provide an expanding arbor including radially outwardly movable keys, wedge means for moving the keys outwardly, and means for limiting the force applied to move the keys outwardly.

It is a further object of the present invention to provide an expanding arbor comprising a pair of generally similar assemblies each of which includes a set of radially movable work engaging keys, wedging cams slidably associated with the keys, springs connected to the wedging means urging them in a direction to cam the keys outwardly, and means responsive to engagement with a workpiece for releasing the wedging means for operational movement by said springs.

Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawing, illustrating preferred embodiments of the invention wherein:

FIGURE 1 is a longitudinal view, partly in section, of an embodiment of the present invention.

FIGURE 2 is a fragmentary section on the line 2-2 of FIGURE 1.

FIGURE 3 is a fragmentary elevational view, partly in section, of a modified camming element suitable for use in the construction of FIGURE 1.

In FIGURE 1 there is shown an arrangement in which the radially outward force is controlled by springs whose effectiveness may be predetermined. In this figure there is also shown a pair of arbor assemblies 70 and 72 which may be identical. The arbor assembly 70 is shown in section and further reference will be to this arbor assembly. Arbor assembly 70 comprises a mounting and housing member 74 having a cylindrical opening 76 therein terminating at its inner end in a wall 78 having a reduced opening 80 extending therethrough. Slidably received in the housing member 74 is the arbor 82 having a reduced portion 84 provided with a plurality of parallel sided radially extending guide slots 86 corresponding in all respects to the guide slots 54 provided in the sleeve 28. The arbor 82 is provided with a cylindrical opening 88 which receives a longitudinally slidable camming element 90 having at its inner end a slightly enlarged head 92 and having at its outer end a reduced portion 94 extending through the opening 80. The camming element 90 is retained in assembled position by a nut 96 and is urged to the right as seen in FIGURE 1 by a compression spring 98. A second compression spring 100 is provided urging the arbor 82 to the right as seen in FIGURE 1.

The housing member 74 includes an annular mounting surface 102 adapted to be engaged by one side of a Workpiece such as the gear indicated in this figure at 104.

The camming element 90 is provided with a plurality of grooves 106. Extending through the slots or elongated openings 86 provided in the reduced portion 84 of the arbor 82 and engaging the inclined bottom camming surfaces of the grooves 106, are keys or wedges 108 retained in assembled position by an expansible garter spring 110.

With the arrangement above described it will be observed that if the arbor assembly 72 is withdrawn to the right, a work gear 104 may be placed on the reduced portion 84 of the arbor 82, at which time it will be supported loosely thereon. Advance of the arbor assembly 72 by a corresponding advance of the tail stock causes the reduced portion '84 of the right hand arbor to enter the right hand end of the gear 104, and locating surface 102 of the housing member 74 will engage the right hand end of the gear and will move it into engagement with the locating surface 102 of the left hand housing member 74. Prior to engagement between the left hand end of the gear 104 and the locating surface 102 of the left hand housing member 74, the left hand end of the gear 104 will engage a shoulder 112 on the left hand arbor 82, which at this time will have moved to the right by the spring into engagement with the radial flange or enlargement 92 on the inner end of the camming element 90. As the tail stock moves to the left the arbor 82 is moved to the left, thus permitting relative movement of the camming element 90 to the right under the influence of the spring 98. Movement of the camming element 90 to the right as seen in FIGURE 1 results in radial outward camming of the keys or wedges 108 and this action is energized by the spring 98 so that the radial force applied through the keys or wedges to the gear 104 is determined by selection of the spring 98. It will of course be apparent that a similar action takes place on the identical structure contained within the right hand housing so that the work gear 104 is first positioned squarely with the axis of the head and tail stock spindles and is thereafter shifted by the wedges or keys 108 into exact axial alignment therewith.

Referring now to FIGURE 3 there is illustrated a variation in the construction of the camming element 90. In this figure the corresponding element is designated and has a head 122 corresponding to the head 92 of the element 90. The camming element 120 differs from the element 90 principally in that the camming grooves 124 are located inwardly from the end of the camming ele ment so that its inner end portion is of uninterrupted complete cylindrical configuration. In either case and in all embodiments of the present invention, the radially outwardly movable keys or wedges are accurately supported, guided and actuated by simultaneous engagement within radial slots extending through the tubular arbor and interfitting elongated camming grooves located in the camming element. With this arrangement the keys or wedges are located with particular accuracy and identical increments of radial outward movement are imparted thereto by axial movement of the camming element 28, 90 or 120.

The drawing and the foregoing specification constitute a description of the improved expanding arbors in such full, clear, concise and exact terms as to enable any person skilled in the art to practice the invention, the scope of which is indicated by the appended claims.

What I claim as my invention is:

1. An expanding arbor construction for an axially elongated rotatable workpiece having cylindrical aligned recesses in opposite ends thereof, said construction comprising two arbor devices movable toward each other to locate and grip the workpiece in located position therebetween, each of said devices comprising a support adjacent the work, a recess in said support, a tubular arbor slidable in said recess, an annular shoulder on said arbor engageable with the adjacent end of the workpiece, said arbor having a reduced end portion dimensioned to enter the recess at the adjacent end of the workpiece, the reduced end of said arbor having axially elongated slots therethrough, a recess in said tubular arbor, a camming element slidable longitudinally in the recess in said tubular arbor and provided with cam surfaces opposite said slots,

keys'in said slots movable radially outwardly by said cam surfaces on relative movement between said camming element and arbor, resilient means interposed between said support and said arbor and between said support and said cammiag element urging said arbor and camming element outwardly from said support toward the adjacent end of a workpiece, stop means limiting outward movement of said arbor and camrning element, the annular shoulders on said arbors being engageable with opposite sides of a workpiece while the reduced end portions there of are loosely received in the recesses at the ends of the workpiece, further approach between said arbor devices resulting in moving both of said arbors relative to their supports vand providingfor radial outward displacement of the keys on both of said arbors by the action of the resilient means interposed between said supports and said camming elements.

2. A construction as defined in claim 1 in which each of said supports comprises an annular end surface rigid therewith and solidly engageable with the adjacent end surface of a workpiece only after the workpiece has been located axially by the annular shoulders on the resiliently urged arbors and located radially by the resiliently urged keys.

No references cited.

WILLIAM W. DYER, IR}, Primary Examiner.

L. VLACHOS, Examiner. 

1. AN EXPANDING ARBOR CONSTRUCTION FOR AN AXIALLY ELONGATED ROTATABLE WORKPIECE HAVING CYLINDRICAL ALIGNED RECESSES IN OPPOSITE ENDS THEREOF, SAID CONSTRUCTION COMPRISING TWO ARBOR DEVICES MOVABLE TOWARD EACH OTHER TO LOCATE AND GRIP THE WORKPIECE IN LOCATED POSITION THEREBETWEEN, EACH OF SAID DEVICES COMPRISING A SUPPORT ADJACENT THE WORK, A RECESS IN SAID SUPPORT, A TUBULAR ARBOR SLIDABLE IN SAID RECESS, AN ANNULAR SHOULDER ON SAID ARBOR ENGAGEABLE WITH THE ADJACENT END OF THE WORKPIECE, SAID ARBOR HAVING A REDUCED END PORTION DIMENSIONED TO ENTER THE RECESS AT THE ADJACENT END OF THE WORKPIECE, THE REDUCED END OF SAID ARBOR HVING AXIALLY ELONGATED SLOTS THERETHROUGH, A RECESS IN SAID TUBULAR ARBOR, A CAMMING ELEMENT SLIDABLE LONGITUDINALLY IN THE RECESS IN SAID TUBULAR ARBOR AND PROVIDED WITH CAM SURFACES OPPOSITE SAID SLOTS, KEYS IN SAID SLOTS MOVABLE RADIALLY OUTWARDLY BY SAID CAM SURFACES ON RELATIVE MOVEMENT BETWEEN SAID CAMMING ELEMENT AND ARBOR, RESILIENT MEANS INTERPOSED BETWEEN SAID SUPPORT AND SAID ARBOR AND BETWEEN SAID SUPPORT AND SAID CAMMING ELEMENT URGING SAID ARBOR AND CAMMING ELEMENT OUTWARDLY FROM SAID SUPPORT TOWARD THE ADJACENT END OF A WORKPIECE, STOP MEANS LIMITING OUTWARD MOVEMENT OF SAID ARBOR AND CAMMING ELEMENT, THE ANNULAR SHOULDERS ON SAID ARBORS BEING ENGAGEABLE WITH OPPOSITE SIDES OF A WORKPIECE WHILE THE REDUCED END PORTIONS THEREOF ARE LOOSELY RECEIVED IN THE RECESSES AT THE ENDS OF THE WORKPIECE, FURTHER APPROACH BETWEN SAID ARBOR DEVICES RESULTING IN MOVING BOTH OF SAID ARBORS RELATIVE TO THEIR SUPPORTS AND PROVIDING FOR RADIAL OUTWARD DISPLACEMENT OF THE KEYS ON BOTH OF SAID ARBORS BY THE ACTION OF THE RESILIENT MEANS INTERPOSED BETWEEN SAID SUPPORTS AND SAID CAMMING ELEMENTS. 